Is fast charging bad for battery health?

[Horstroad]

A few years back LTT made an episode to explain battery wear and told us to not charge our phone over 80% to keep the battery healthy for longer.

 

After I had to replace my last phone because the battery died after just 2 years (I always had it plugged in over night), I really took care of the next one, my current phone. With some exceptions (I guess a maximum of 10 occasions for the upper limit and 40 for the lower) my phone always stayed between 15% and 75% of the total battery capacity. Still the battery has an estimated capacity of only 81% after three years of usage.

 

As I will be getting a new phone in a few days, I was wondering whether in addition to restricting how much I charge or discharge my phone, if would it be advantageous to not use fast charging when I can avoid it. After all I don't always need my phone to be recharged within half an hour. For example when I'm at my desk at home. Does fast charging wear the battery more, or is the effect of charging speed negligible?

 

Is there any other advice or best practice to follow regarding battery health?

[Helpful Tech Witch]

Batteries go bd over time, 81% is fine on a phone after 3 years. SHould see the capacity of some 3 year old laptops....

Fast charging can make it go bad, especially the ones that push like 80w through the battery. 

[Levent]

4 minutes ago, Horstroad said:

Does fast charging wear the battery more

Yes, fast charging results in more heat output, thus more strain on the battery [Edit: I should also mention that charging systems are more complex nowadays and they usually start to throttle when battery or the charger starts getting too hot].

4 minutes ago, Horstroad said:

is the effect of charging speed negligible?

Definitely not, I got a 18W QC3 device it is almost 4 times faster than 5W charging. I can also easily overwhelm the 5W charging for example when I am driving and google maps is running.

[Horstroad]

2 hours ago, HelpfulTechWizard said:

Batteries go bd over time, 81% is fine on a phone after 3 years. SHould see the capacity of some 3 year old laptops....

Fast charging can make it go bad, especially the ones that push like 80w through the battery. 

Well even though one could consider it as "not bad", I would like to improve on that on my next phone, if possible. And using regular charging instead of fast charging, when not needed, isn't an inconvenience for me.

2 hours ago, Levent said:

Yes, fast charging results in more heat output, thus more strain on the battery [Edit: I should also mention that charging systems are more complex nowadays and they usually start to throttle when battery or the charger starts getting too hot].

I don't want to rely only on the charging management of the phone. If I can reduce wear on the battery by other means (and it's not an inconvenience) I'm willing to do so.

3 hours ago, Levent said:

Definitely not, I got a 18W QC3 device it is almost 4 times faster than 5W charging. I can also easily overwhelm the 5W charging for example when I am driving and google maps is running.

I was talking about the effects of fast charging on battery health. Of course I know that a beefier charger charges my phone faster and that weak ones can't keep up.

 

 

The question was whether a 18W charger will wear my battery less than a 30W charger.

[Levent]

8 minutes ago, Horstroad said:

The question was whether a 18W charger will wear my battery less than a 30W charger.

This has been answered in the Qualcomm QC FAQ.

https://www.qualcomm.com/products/features/quick-charge/faq

TLDR: Depends on the implementation, but most likely not.

 

 

I am not sure if you are aware but phones do not charge to 100% using QC all the way. If the device is at room temperature, it will charge to around 60% with full blast then start dialing down the current and the voltage. If device is out of the acceptable parameters, it will either not charge at maximum speed or will stop before it's regular threshold. 

 

Unless you are getting non Qualcomm phones/tablets that do not have QC set up properly and/or using shitty chargers, this is not something you should lose any sleep over it.

[OhioYJ]

2 hours ago, Horstroad said:

The question was whether a 18W charger will wear my battery less than a 30W charger.

 

To think the "fast" charger I use with my phone is ~ 5W....  Nothing says you have to use a high power charger with your device. I've always slow charged all my devices. I believe my 8T came with a 65W charger, never used it.